U.S. patent application number 15/517575 was filed with the patent office on 2017-10-26 for display device.
The applicant listed for this patent is Sharp Kabushiki Kaisha. Invention is credited to Kazutoshi KIDA, Tomohiro KIMURA, Jean MUGIRANEZA, Hiroyuki OGAWA, Yasuhiro SUGITA.
Application Number | 20170308200 15/517575 |
Document ID | / |
Family ID | 55653127 |
Filed Date | 2017-10-26 |
United States Patent
Application |
20170308200 |
Kind Code |
A1 |
MUGIRANEZA; Jean ; et
al. |
October 26, 2017 |
DISPLAY DEVICE
Abstract
A display device is provided in which a configuration of first
electrodes (4) in a first area (R1) that overlaps a display area
(AA) of a touch panel (2), and a configuration of first electrodes
(6) in a second area (R2) outside the first area, are different
from each other. In the second area (R2), at least one electrode
pad (6-1a, 6-2a) of the first electrodes (6) is arranged so as to
be opposed to one second electrode (7a).
Inventors: |
MUGIRANEZA; Jean; (Sakai
City, JP) ; SUGITA; Yasuhiro; (Sakai City, JP)
; KIDA; Kazutoshi; (Sakai City, JP) ; OGAWA;
Hiroyuki; (Sakai City, JP) ; KIMURA; Tomohiro;
(Sakai City, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Sharp Kabushiki Kaisha |
Sakai City, Osaka |
|
JP |
|
|
Family ID: |
55653127 |
Appl. No.: |
15/517575 |
Filed: |
October 5, 2015 |
PCT Filed: |
October 5, 2015 |
PCT NO: |
PCT/JP2015/078239 |
371 Date: |
April 7, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G06F 2203/04111
20130101; G02F 1/134336 20130101; G02F 1/13338 20130101; H03K
17/962 20130101; G06F 3/044 20130101; G06F 2203/04108 20130101;
H03K 17/955 20130101; G06F 3/0416 20130101 |
International
Class: |
G06F 3/044 20060101
G06F003/044; G02F 1/1333 20060101 G02F001/1333; G02F 1/1343
20060101 G02F001/1343 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 10, 2014 |
JP |
2014-208754 |
Claims
1: A display device comprising a display panel that has a display
area that displays an image, and a touch panel stacked on the
display panel, wherein the touch panel includes: a plurality of
first electrodes that extend in a first direction; a plurality of
second electrodes that extend in a second direction that intersects
with the first direction; and a control unit that detects contact
or approach of an object by detecting capacitances between the
first electrodes and the second electrodes or respective
capacitances of the first electrodes and the second electrodes,
wherein, in the touch panel, a shape of the first electrode in a
first area that overlaps the display area, and a shape of the first
electrode in a second area outside the first area, are different,
and in the second area, the first electrode includes at least one
electrode pad, and the electrode pad of the first electrode is
arranged so as to be opposed to one of the second electrodes.
2: The display device according to claim 1, wherein, in the second
area, the first electrode includes two or more electrode pads, and
the two or more electrode pads of the first electrode are arranged
so as to be opposed to one of the second electrodes, and the two or
more electrode pads of the first electrode, which are arranged so
as to be opposed to one of the second electrodes in the second
area, are connected through individually provided lines,
respectively, to the control unit.
3: The display device according to claim 2, wherein the two or more
electrode pads of the first electrode, which are arranged so as to
be opposed to one of the second electrodes in the second area, are
arrayed in the first direction.
4: The display device according to claim 2, wherein at least one of
the second electrodes is formed so as to extend from an inner side
of the first area toward the second area, and two or more electrode
pads of the first electrode are arrayed in the first direction so
as to be opposed to the second electrode extending toward the
second area.
5: The display device according to claim 3, wherein, in the first
area, the two or more electrode pads of the first electrode are
arrayed in the first direction so as to be opposed to one of the
second electrodes, and the two or more electrode pads of the first
electrode in the first area are connected to one line that extends
in the first direction.
6: The display device according to claim 1, wherein a material of
the first electrodes or the second electrodes in the first area is
different from a material of the first electrodes or the second
electrodes in the second area.
7: The display device according to claim 1, wherein the control
unit detects the capacitances between the first electrodes and the
second electrodes by a mutual capacitance method in the first area,
and detects the capacitances of the first electrodes and the second
electrodes by a self-capacitance method in the second area.
8: The display device according to claim 1, further comprising
third electrodes that are provided so as to be opposed to the first
electrodes or the second electrodes, in the second area.
9: An electronic apparatus comprising the display device according
to claim 1.
Description
TECHNICAL FIELD
[0001] The present disclosure relates to a technique of detecting
contact or approach of an object, used in a display device having a
touch panel.
BACKGROUND ART
[0002] A display device such as, for example, a smartphone or a
tablet includes a touch panel (referred to as a touch sensor or a
touch screen in some cases). The touch panel has electrodes for
detecting contact or approach of an object. With such a touch
panel, a user interface that enables an input operation with
respect to an image displayed on a display device can be
realized.
[0003] In recent years, a variety of forms of user interfaces have
been proposed. For example, the specification of US Patent
Application Publication No. 2010/0134423 discloses that a sensor is
arranged on an edge of an apparatus so that the apparatus can
determine whether the apparatus is in the left hand and/or the
right hand of the user. Further, the specification of US Patent
Application Publication No. 2013/0300697 discloses a bended display
that enables operations with respect to a main area of a front
surface of a portable device and a sub area of a side surface of
the portable device.
PRIOR ART DOCUMENT
Patent Document
Patent Document 1: US Patent Application Publication No.
2010/0134423
Patent Document 2: US Patent Application Publication No.
2013/0300697
SUMMARY OF THE INVENTION
Problem to be Solved by the Invention
[0004] On a touch panel, electrodes for detecting an object are
arranged in an area that overlaps a display area. In an area
outside the area that overlaps the display area, for example, in a
frame area, electrodes for detecting an object can be arranged as
well. This makes it possible to detect contact or approach of an
object outside the display area as well. In the area outside the
area that overlaps the display area, however, lead-out lines that
connect the electrodes arranged in the area that overlaps the
display area with a signal processing unit are also arranged
additionally in many cases. If many constituent elements such as
electrodes and lines are arranged on the touch panel, outside the
area that overlaps the display in this way, narrowing the frame is
inhibited, the detection performance in an area outside the display
area is limited, and this also causes the complication of the
production process, the materials, the configuration, the
processing process, and the like. This was found by the inventors
of the present invention. To cope with these, the specification of
the present application discloses a technique for arranging
constituent elements of a touch panel efficiently in an area
outside an area that overlaps the display area.
Means to Solve the Problem
[0005] A display device of the present disclosure includes a
display panel that has a display area that displays an image, and a
touch panel stacked on the display panel. The touch panel includes:
a plurality of first electrodes that extend in a first direction; a
plurality of second electrodes that extend in a second direction
that intersects with the first direction; and a control unit that
detects contact or approach of an object by detecting capacitances
between the first electrodes and the second electrodes. In the
touch panel, a shape of the first electrode in a first area that
overlaps the display area, and a shape of the first electrode in a
second area outside the first area, are different. In the second
area, the first electrode includes at least one electrode pad, and
the electrode pad is arranged so as to be opposed to one of the
second electrodes.
Effect of the Invention
[0006] According to the present disclosure, constituent elements of
a touch panel can be arranged efficiently in an area outside an
area that overlaps a display area.
BRIEF DESCRIPTION OF DRAWINGS
[0007] FIG. 1 is a cross-sectional view illustrating an exemplary
configuration of a display device in Embodiment 1.
[0008] FIG. 2 is a plan view illustrating an exemplary
configuration of a touch panel 2 in FIG. 1, viewed in the direction
indicated by arrow II.
[0009] FIG. 3 illustrates a modification example of a
configurations of first electrodes and second electrodes in an area
R1 and areas R2.
[0010] FIG. 4 is a cross-sectional view taken along line A-A in
FIG. 3.
[0011] FIG. 5 illustrates another modification example of the
configuration of the first electrodes and the second electrodes in
the area R1 and the areas R2.
[0012] FIG. 6A illustrates a detailed exemplary configuration of
the first electrodes 6 in the area R2.
[0013] FIG. 6B illustrates an exemplary case where two columns of
the first electrode pads 6-1a, 6-2a, and 6-3a illustrated in FIG.
6A are provided.
[0014] FIG. 7A illustrates an exemplary modification of the first
electrode pads.
[0015] FIG. 7B illustrates another exemplary modification of the
first electrode pads.
[0016] FIG. 7C illustrates still another exemplary modification of
the first electrode pads.
[0017] FIG. 7D illustrates still another exemplary modification of
the first electrode pads.
[0018] FIG. 7E illustrates still another exemplary modification of
the first electrode pads.
[0019] FIG. 7F illustrates still another exemplary modification of
the first electrode pads.
[0020] FIG. 8 illustrates an exemplary configuration in a case
where the first electrodes 4, 6 and the second electrodes 5, 7
illustrated in FIG. 2 are applied to a non-rectangular touch
panel.
[0021] FIG. 9 illustrates an exemplary configuration in which the
second electrodes 5 in the area R1 and the second electrodes 7 in
the areas R2 are independently provided.
[0022] FIG. 10A is a cross-sectional view illustrating an exemplary
configuration in a case where third electrodes are provided on the
touch panel 2 illustrated in FIGS. 3 and 4.
[0023] FIG. 10B illustrates an arrangement of the third electrodes
8 on the touch panel 2 illustrated in FIG. 10A, when viewed in the
direction II vertical to the display surface.
[0024] FIG. 11 illustrates a exemplary modification of the first
electrodes 6 and the second electrodes 7 in the areas R2.
[0025] FIG. 12 illustrates a modification example of the touch
panel illustrated in FIG. 11.
[0026] FIG. 13 illustrates an exemplary modification of electrode
pads of the first electrodes in the area R2 in the configuration
illustrated in FIG. 1.
EMBODIMENTS
[0027] A display device according to one embodiment of the present
invention includes a display panel that has a display area that
displays an image, and a touch panel stacked on the display panel.
The touch panel includes: a plurality of first electrodes that
extend in a first direction; a plurality of second electrodes that
extend in a second direction that intersects with the first
direction; and a control unit that detects contact or approach of
an object by detecting capacitances between the first electrodes
and the second electrodes or respective capacitances of the first
electrodes and the second electrodes. In the touch panel, a shape
of the first electrode in a first area that overlaps the display
area, and a shape of the first electrode in a second area outside
the first area, are different. In the second area, the first
electrode includes at least one electrode pad, and the electrode
pad is arranged so as to be opposed to one of the second
electrodes. This makes it possible to efficiently arrange the first
and second electrodes in the second area. This therefore makes it
possible to efficiently arrange constituent elements of the touch
panel in an area outside an area that overlaps the display
area.
[0028] In the second area, the first electrode may include two or
more electrode pads. In this case, in the second area, the two or
more electrode pads of the first electrode can be arranged so as to
be opposed to one of the second electrodes. The two or more
electrode pads of the first electrode, which are arranged so as to
be opposed to one of the second electrodes in the second area, are
connected through individually provided lines, respectively, to the
control unit. This allows the two or more first electrodes
controlled through different lines to be arranged so as to be
opposed to one second electrode in the second area. This therefore
enables more efficient electrode arrangement in the second
area.
[0029] The two or more electrode pads of the first electrode, which
are arranged so as to be opposed to one of the second electrodes in
the second area, can be arrayed in the first direction. In this
configuration, in the second area, the two or more electrode pads
of the first electrode, which are opposed to the one of the second
electrodes, are arranged in the first direction. These electrode
pads of the first electrode are connected with the control unit
respectively through independent lines. With this configuration,
signals input to or output from the electrode pads of the first
electrode can be controlled or processed separately. In other
words, regarding one second electrode, capacitances corresponding
to two or more positions in the first direction can be detected.
This makes it possible to increase the capacitance detection points
in the first direction, without increasing the second electrodes.
This therefore makes it possible to efficiently arrange the
constituent elements of the touch panel in an area outside an area
that overlaps the display area.
[0030] In the above-described configuration, at least one of the
second electrodes can be formed so as to extend from an inner side
of the first area toward the second area, and two or more electrode
pads of the first electrode can be arrayed in the first direction
so as to be opposed to the second electrode extending toward the
second area. This provides such a configuration that at least part
of the second electrodes in the first area are connected with at
least part of the second electrodes in the second area. In other
words, in the first area and in the second area, at least part of
the electrodes for detecting an object can be shared. This makes it
possible to reduce the members of the touch panel. Further, this
makes it easier to detect a series of actions of an object across
the first area and the second area.
[0031] The above-described configuration can be such that, in the
first area, the two or more electrode pads of the first electrode
are arrayed in the first direction so as to be opposed to one of
the second electrodes, and the two or more electrode pads of the
first electrode in the first area are connected to one line that
extends in the first direction. This allows the detection accuracy
in the first direction in the first area, and the detection
accuracy in the first direction in the second area, to be
different. This therefore makes it possible that, for example, in
both of the first area and the second area, respective detection
properties suitable for the object detection in the respective
areas can be realized.
[0032] The above-described configuration can be such that a
material of the first electrodes or the second electrodes in the
first area is different from a material of the first electrodes or
the second electrodes in the second area. This allows the first
area and the second area to have different detection properties.
This therefore makes it possible to achieve appropriate detection
properties respectively in the first area and the second area.
[0033] The above-described configuration can be such that the
control unit detects the capacitances between the first electrodes
and the second electrodes by a mutual capacitance method in the
first area, and detects the capacitances of the first electrodes
and the second electrodes by a self-capacitance method in the
second area. This makes it possible that in the second area,
detection performance different from that in the first area can be
achieved. For example, in the first area, contact of an object is
detected, and in the second area, detection (hover detection) of an
object at a position separated from the display device surface,
fingerprint detection, and the like can be performed.
[0034] The above-described configuration may be such that the
display device further includes third electrodes that are provided
so as to be opposed to the first electrodes or the second
electrodes, in the second area. This makes it possible to, for
example, add a function of detecting an object based on
capacitances between the third electrodes and the first electrodes
or the second electrodes. Alternatively, the third electrodes and
the first electrodes or the second electrodes can be caused to
function as electrodes for a sensor other than the touch panel.
With this, the complication of the configuration in the second area
can be suppressed, the object detection performance can be
enhanced, and another sensor function can be added.
[0035] The embodiments of the present invention encompass various
types of electronic apparatuses equipped with the above-described
display device.
[0036] The following describes embodiments of the present invention
in detail, while referring to the drawings. Identical or equivalent
parts in the drawings are denoted by the same reference numerals,
and the descriptions of the same are not repeated. To make the
description easy to understand, in the drawings referred to
hereinafter, the configurations are simplified or schematically
illustrated, or a part of constituent members are omitted. Further,
the dimension ratios of the constituent members illustrated in the
drawings do not necessarily indicate the real dimension ratios.
Embodiment 1
(Exemplary Configuration of Touch Panel)
[0037] FIG. 1 is a cross-sectional view illustrating an exemplary
configuration of a display device 10 in Embodiment 1. FIG. 2 is a
plan view illustrating an exemplary configuration of a touch panel
2 in FIG. 1, viewed in the direction indicated by arrow II. FIG. 1
illustrates a cross section taken along line A-A in FIG. 2.
[0038] In the example illustrated in FIG. 1, the display device 10
includes a display panel 1, and a touch panel 2 stacked on the
display panel 1. The display panel 1 has a display area AA in which
an image is displayed. The display area AA is an area where pixels
for displaying an image are arranged. The display panel 1 may be in
the form of, for example, a liquid crystal panel, though it is not
limited particularly. The liquid crystal panel includes an active
matrix substrate, a counter substrate, and a liquid crystal layer
provided between the active matrix substrate and the counter
substrate.
[0039] The touch panel 2 is stacked on the display panel 1 so as to
cover the display area AA. Light outgoing from pixels of the
display area AA passes through the touch panel 2, and outgoes from
the surface of the touch panel 2. In the example illustrated in
FIG. 1, an air gap is provided between the display panel 1 and the
touch panel 2.
[0040] As illustrated in FIGS. 1 and 2, the touch panel 2 includes
a transparent substrate 2b, first electrodes 4, 6, second
electrodes 5, 7, and a transparent cover 2a. The first electrodes
4, 6 and the second electrodes 5, 7 are provided on the transparent
substrate 2b. The transparent cover 2a is provided so as to cover
the first electrodes 4, 6 and the second electrodes 5, 7. By
detecting a capacitance between these first and second electrodes,
the touch panel 2 detects contact or approach of an object such as
a finger, a pen, or the like.
[0041] In the example illustrated in FIG. 2, on the touch panel 2,
in an area R1 that overlaps the display area AA (an example of a
first area), a plurality of first electrodes 4 (4-1 to 4-4)
extending in a first direction (in the present example, the
longitudinal direction of the drawing), and a plurality of second
electrodes 5 (5-1 to 5-6) extending in a direction different from
the first direction in the area R1 (in the present example, the
horizontal direction of the drawing), are arranged. The first
electrodes 4 and the second electrode 5 are not electrically
connected, and are insulated from each other.
[0042] The surface in the area R1 on which the first and second
electrodes 4 and 5 are provided, and the surfaces in the areas R2
on which the first and second electrodes 6 and 7 are provided can
be parallel to the display surface of the display panel 1. The
first and second electrodes 4 and 5 in the area R1 and the first
and second electrodes 6 and 7 in the areas R2 are thus formed on an
identical surface or parallel surfaces, which prevents the
electrode forming steps from becoming complicated.
[0043] Each of the first electrodes 4 in the area R1 is formed with
a plurality of first electrode pads 4a arrayed in the first
direction, and first connection lines 4b that connect adjacent ones
of the first electrode pads 4a. Each of the second electrodes 5 in
the area R1 is also formed with a plurality of second electrode
pads 5a arrayed in the second direction, and second connection
lines 5b that connect adjacent ones of the second electrode pads
5a. The first electrode pads 4a and the second electrode pads 5a
are arranged so as to be adjacent to each other.
[0044] In the example illustrated in FIG. 2, a plurality of
rectangular electrode pads 4a and 5a are arranged in a matrix that
has rows and columns in the area R1. The first electrode pads 4a
arrayed in the longitudinal direction, i.e., the vertical
direction, of the display screen form columns. The second electrode
pads 5a arrayed in the transverse direction, i.e., the horizontal
direction, of the display screen, form rows. In the present
embodiment, the first direction is the column direction
(longitudinal direction), and the second direction is the row
direction (transverse direction). The first electrode 4 of each
column is connected to a touch panel controller 11 (TP controller)
through a first line 4c. The second electrode 5 of each row is
connected to the TP controller 11 through a second line 5c.
[0045] The configuration of the first electrode 4 in the area R1,
and the configuration of the first electrode 6 in the areas R2 (one
example of the second area) outside the area R1, are different. The
second electrodes 5 (5-1 to 5-6) in the area R1 are connected to
the second electrodes 7 (7-1 to 7-6) in the areas R2 outside the
area R1, respectively. In the area R2, each second electrode 7
includes second electrode pads 7-1a to 7-6a (hereinafter referred
to as second electrode pads 7a when referred to generally).
Respective first electrode pads 6-1a and 6-2a of the two first
electrodes 6 are arranged so as to be opposed to one second
electrode pad 7a in the first direction. The two first electrode
pads 6-1a and 6-2a opposed to the one second electrode pad 7a are
arrayed in the first direction. In other words, the two first
electrodes 6-1a and 6-2a are arranged on the sides of one second
electrode 7a, respectively, in such a manner that one second
electrode 7a is interposed between the two first electrodes 6-1a
and 6-2a in the first direction.
[0046] In the area R2, the two first electrode pads 6-1a and 6-2a
opposed to one second electrode pad 7a are connected to different
lines 6-1c and 6-2c, respectively. Both of these lines 6-1c and
6-2c extend in the first direction, and are connected to the TP
controller 11. In other words, the two first electrode pads 6-1a
and 6-2a opposed to the one second electrode pad 7a are connected
to the TP controller 11 through the lines 6-1c and 6-2c, which are
provided individually. With this configuration, the first electrode
6-1a is connected to the TP controller 11 through the line 6-1c,
and the first electrode 6-2a is connected thereto through the line
6-2c. To one line 6-1c, a plurality of the first electrode pads
6-1a are connected. The plurality of first electrode pads 6-1a
connected to one line 6-1 are opposed to different second electrode
pads 7a, respectively.
[0047] The TP controller 11 is an exemplary control unit that
detects capacitances between the first electrodes 4, 6 and the
second electrodes 5, 7, or respective capacitances of the first
electrodes 4, 6 and the second electrodes 5, 7. In the present
example, the TP controller 11 controls voltage signals of the first
electrodes 4, 6 and the second electrodes 5, 7, so as to detect
changes in the capacitances between adjacent ones of the first
electrodes 4, 6 and the second electrodes 5, 7. The TP controller
11 is capable of identifying a position of an object that
approaches or is in contact with the touch panel 2 based on the
detected changes in the capacitances. The TP controller 11 is an
exemplary control unit that detects contact or approach of an
object based on the capacitances between the first electrodes and
the second electrodes. The TP controller can be formed with, for
example, a semiconductor chip (not illustrated) that is provided on
the touch panel 2, or on an FPC (not illustrated) connected to the
touch panel 2.
[0048] In the present embodiment, in the area R1, two first
electrode pad 4a that are arrayed in the first direction and
opposed to one second electrode pad 5a, are connected to one line
4b that extends in the first direction. In contrast, in the area
R2, two electrode pads 6-1a and 6-2a that are arrayed in the first
direction and opposed to one second electrode pad 7a are connected
to two lines 6-1c and 6-2c, respectively, which extend in the first
direction. This allows the detection accuracy (resolution) in the
first direction in the area R2, and the detection accuracy
(resolution) in the second direction in the area R1, to be
different.
[0049] In the example illustrated in FIG. 2, in a part of the area
R2 that corresponds to one row of the second electrode 5 in the
area R1, one second electrode pad 7a and two first electrode pads
6-1a and 6-2 opposed to the foregoing electrode pad 7a are
provided. These two first electrode pads 6-1a and 6-2a are
connected to different lines 6-1c and 6-2c, respectively, and are
arranged so as to be arrayed in the first direction. The resolution
in the first direction in the area R2, therefore, can be set to
around twice the resolution in the first direction in the area
R1.
[0050] Besides, with the above-described configuration, only a
smaller number of lines may be added for improving the resolution.
More specifically, in the above-described example, in order to
achieve the resolution that is around twice, two lines 6-1c and
6-2c are provided with respect to the first electrode pads 6-1a and
6-2a, in each of the two areas R2 on the right and left sides of
the display area AA. Since this results in that one line is added
in each of the two areas R2 on the right and left sides, the number
of added lines as a whole is only two. In other words, in order to
increase the resolution in the first direction in the two areas R2
to n times, it is required to add only 2(n-1) lines. In contrast,
for example, in a case where the resolution is increased to n times
by increasing the second electrodes 7 in the areas R2, it is
required to increase the number of lines to n times. In this way,
in some cases, an increase in the number of lines makes forming a
narrower frame difficult, or leads to the deterioration of
detection performance. On the other hand, with the above-described
configuration, there is almost no increase in the number of lines,
which makes it possible to achieve a narrower frame while
suppressing the deterioration of detection performance.
[0051] More specifically, in the area R2, each of the two first
electrode pads 6-1a, 6-2a and the second electrode pad 7a has two
sides parallel to the second direction, and the second electrode
pad 7a and the two first electrode pads 6-1a, 6-2a opposed to the
electrode pad 7a are provided in such a manner that sides of the
two first electrode pads 6-1a, 6-2a adjacent to the electrode pad
7a are opposed to the above-mentioned two sides of the second
electrode pad 7a, respectively. Further, the density at which the
first electrode pads 6-1a and 6-2a are arranged in the first
direction in the area R2, and the density at which the first
electrode pads 4a are arranged in the first direction in the area
R1, are different. This allows the area R1 and the area R2 to have
further different detection properties.
[0052] The materials of the first electrodes 4 and the second
electrodes 5 in the area R1, and the materials of the first
electrodes 6 and second electrodes 7 in the area R2 may be
different. For example, the materials of the first electrode 4, 6
and the second electrode 5, 7 can be selected so that the first
electrodes 6 and the second electrodes 7 in the area R2 have lower
electric resistances as compared with electric resistances of the
first electrodes 4 and the second electrodes 5 in the area R1. In
this way, electric properties of the first electrodes 4 and the
second electrodes 5 in the area R1 are made different from those of
the first electrodes 6 and the second electrodes 7 in the area R2,
whereby the object detection properties in the area R1 and those in
the area R2 can be made different.
[0053] As one example, the first electrodes 4 and the second
electrodes 5 in the area R1 can be formed with a transparent
conductive material such as ITO. The first electrodes 6 and the
second electrodes 7 in the area R2 can be formed with a metal
having a lower resistance than that of the transparent conductive
material, such as Al, Co, or Mo. Further, the electrodes in the
area R2 can be formed with a metal mesh. By using low-resistance
lines for the first electrodes 6 and the second electrodes 7 in the
area R2 in this way, noise components in the signals passing
through the electrodes in the area R2 can be reduced. This enables
high-performance detection of an object in the area R2. For
example, in the area R2, high-performance and highly-sensitive
detection than that in area R1 is enabled. Alternatively, the
configuration of the area R2 may be such that hover detection is
possible. In the hover detection, the position of an object
approaching thereto can be detected without touch on the touch
panel 2.
[0054] The configuration of the first electrodes 4, 6 and the
second electrodes 5, 7 illustrated in FIGS. 1 and 2 are merely an
example, and the configuration of the first electrodes and the
second electrodes is not limited to that of the above-described
example. In the above-described configuration, the second electrode
pads 7a and the first electrode pads 6-1a and 6-2a are formed in
the same layer in the area R2, and are opposed to each other in the
first direction. In contrast, for example, the second electrode
pads 7a and the first electrode pads 6-1a and 6-2a may be formed in
different layers, and may be opposed to each other with interlayer
insulating films being interposed. Similarly, in the area R1 as
well, the first electrodes 4 and the second electrodes 5 may be
arranged in different layers. Further, the number of second
electrode pads arranged so as to be opposed to one second electrode
in the area R2 is not limited to two, and three or more second
electrode pads may be arranged.
(Modification Example 1 of Electrode Configuration)
[0055] FIG. 3 illustrates a modification example of the
configurations of the first electrodes and the second electrodes in
the area R1 and the areas R2. FIG. 4 is a cross-sectional view
taken along line A-A in FIG. 3. In the example illustrated in FIGS.
3 and 4, in the area R1, the first electrodes 4 and the second
electrodes 5 are formed in different layers with an insulating
layer being interposed therebetween. In the area R2 as well, the
first electrodes 6 and the second electrodes 7 are formed in
different layers with an insulating layer being interposed
therebetween. In the area R1, a plurality of the second electrodes
5 (5-1 to 5-6) extending in the second direction are arrayed in the
first direction. An insulating layer is provided so as to cover the
first electrodes 5. On this insulating layer, a plurality of the
first electrodes 4 (4-1 to 4-4) extending in the first direction
are formed so as to intersect with the second electrodes 5, when
viewed in a direction vertical to the display surface.
[0056] The second electrodes 5 (5-1 to 5-6) in the area R1 extend
to the area R2 outside the area R1, thereby forming the second
electrodes 7 (7-1 to 7-6) in the area R2. With respect to one
second electrode 7 in the area R2, a plurality of first electrode
pads 6-1a, 6-2a, and 6-3a are formed at positions that overlap the
foregoing second electrode 7 in the direction vertical to the
display surface. In other words, with respect to one second
electrode 7, a plurality of (three in the present example)
electrode pads 6-1a to 6-3a are arranged so as to be opposed to the
foregoing second electrode 7 with an insulating layer being
interposed therebetween. The electrode pads 6-1a to 6-3a opposed to
the one second electrode 7 are arrayed in the first direction. To
these electrode pads 6-1a, 6-2a, and 6-3a, different lines 6-1c,
6-2c, and 6-3c are connected, respectively. The lines 6-1c, 6-2c,
and 6-3c are connected to the TP controller 11. To one line 6-1c, a
plurality of the first electrode pads 6-1a are connected. The first
electrode pads 6-1a connected to the one line 6-1c are arranged so
as to be opposed to different second electrodes 7,
respectively.
[0057] In the example illustrated in FIG. 3, in a part of the area
R2 that corresponds to one row of the second electrode 5 in the
area R1, one second electrode 7 and three first electrode pads
6-1a, 6-2a, and 6-3a opposed to the foregoing second electrode 7
are provided. These three first electrode pads 6-1a, 6-2a, and 6-3a
are connected to different lines 6-1c, 6-2c, and 6-3c,
respectively, and are arrayed in the first direction. The
resolution in the first direction in the area R2, therefore, can be
set to around three times the resolution in the first direction in
the area R1. In this case, only four lines in total may be added in
the two areas R2 on the right and left sides to the area R1.
(Modification Example 2 of Electrode Configuration)
[0058] FIG. 5 illustrates another modification example of a
configuration of first electrodes and second electrodes in an area
R1 and areas R2. In the example illustrated in FIG. 5, the
electrode configuration in the area R1 is identical to the
configuration of the first electrodes 4 and the second electrodes 5
in the area R1 illustrated in FIG. 2. In the area R2, the second
electrodes 7-1 to 7-6 and the first electrode pads 6-1a, 6-2a, and
6-3a are formed in different layers with an insulating layer being
interposed therebetween. With respect to one second electrode 7-1,
three first electrode pads 6-1a, 6-2a, and 6-3a arrayed in the
first direction are provided so as to be opposed to the second
electrode 7-1. These three first electrode pads 6-1a, 6-2a, and
6-3a are connected to different lines 6-1c, 6-2c, and 6-3,
respectively. The first electrodes 6-1a to 6-3a in the area R2 and
the lines 6-1c to 6-3c connected thereto can be formed in the same
manner as illustrated in FIG. 3.
[0059] Thus, the first electrodes and the second electrodes are
formed so that the patterns thereof in the area R1 and in the area
R2 are different as illustrated in FIG. 5, whereby the detection
performance in the area R1 and the detection performance in the
area R2 can be made different from each other. For example, by
making the patterns of the first electrodes and the second
electrodes different, the properties of signals detected by the
first electrodes or the second electrodes can be made
different.
(Detailed Modification Examples of First Electrodes 6 in Area
R2)
[0060] FIG. 6A illustrates a detailed exemplary configuration of
first electrodes 6 in the area R2. In the example illustrated in
FIG. 6A, in an area that overlaps one second electrode 7-1a in plan
view, three first electrode pads 6-1a, 6-2a, and 6-3a arrayed in
the first direction are provided. Each of the first electrode pads
6-1a, 6-2a, and 6-3a is formed in a rectangular shape having long
sides extending in the second direction. To a short side on one
side of the first electrode pad 6-1a, a line 6-3c is connected. The
line 6-3c extends in the first direction, and is connected to a
plurality of the first electrode pads 6-1a that are opposed to the
other second electrodes 7-2a to 7-5a, respectively. In other words,
the plurality of first electrode pads 6-1a opposed to the
individual second electrodes 7-2a to 7-5a, respectively, are
arrayed in the first direction, and are connected to the one line
6-1c. To short sides of the first electrode pads 6-2a and 6-3a on
the side opposite to the sides thereof connected to the line 6-1c,
the lines 6-2c and 6-3c are connected, respectively. The lines 6-2c
and 6-3c extend in the first direction. The lines 6-2c and 6-3c are
connected to a plurality of first electrode pads 6-2a and 6-3a,
respectively, the first electrode pads 6-2a being opposed to the
individual second electrodes 7-1a to 7-5a, respective, and so being
the first electrode pads 6-3a. The line 6-2c and the line 6-3c are
not electrically connected, and are insulated from each other.
[0061] FIG. 2, FIG. 3, FIG. 5 and FIG. 6A illustrate examples in
which the first electrode pads 6 of one column are arranged in the
area R2, but the arrangement of the first electrode pads 6 is not
limited to this. For example, the first electrode pads 6 of two or
more columns can be arranged in the area R2. As one example, FIG.
6B illustrates an example in which the first electrode pads 6-1a,
6-2a, and 6-3a illustrated in FIG. 6A are arranged in two columns.
In the example illustrated in FIG. 6B, with respect to one second
electrode 7-1a extending in the second direction, two columns each
of which is composed of three first electrode pads 6-1a, 6-2a, and
6-3a opposed to the second electrode 7-1a, as well as the lines
6-1c, 6-2c, 6-3c thereof, are formed so as to be arrayed in the
second direction.
[0062] Further, the number of the first electrode pads in the area
R2 that are opposed to one second electrode 7a and are arrayed in
the first direction is not limited to two or three as is the case
with the above-described examples. For example, four or more first
electrode pads may be arranged so as to be opposed to one second
electrode 7a and arrayed in the first direction.
[0063] As one example, FIG. 7A illustrates a configuration in which
four first electrode pads 6-1a to 6-4a opposed to one second
electrode 7a are arrayed in the first direction in an area that
overlaps the second electrode 7a in plan view. FIG. 7B illustrates
a configuration in which two columns each of which is composed of
the first electrode pads 6-1a to 6-4a illustrated in FIG. 7A are
arrayed in the second direction.
[0064] As still another example, FIG. 7C illustrates a
configuration in which two first electrode pads 6-1a and 6-2a
opposed to one second electrode 7a are arrayed in the first
direction in an area that overlaps the second electrode 7a in plan
view. FIG. 7D illustrates a configuration in which two columns each
of which is composed of the first electrode pads 6-1a and 6-2a
illustrated in FIG. 7C are arrayed in the second direction.
[0065] Further, the shape of the first electrode 6 is not limited
to those of the above-described examples. FIGS. 7E and 7F
illustrate examples in cases where each of the first electrode pads
6 in the area R2 is formed in a triangular shape. In the examples
illustrated in FIGS. 7E and 7F, a plurality of first electrode pads
6-1a and 6-2a in the area R2, which are opposed to one second
electrode 7a, are formed in triangular shapes.
[0066] In FIG. 7F, the first electrode pads 6-1a and 6-2a are
arranged in such a manner that the hypotenuses of the two right
angled triangles that form the first electrode pads 6-1a, and the
two equal-length sides of the isosceles triangle that forms the
first electrode pad 6-2a, are opposed in the first direction.
[0067] In the example illustrated in FIG. 7F, the first electrode
pads 6-1a and 6-2a are arranged in such a manner that the
hypotenuse of the right angled triangle that forms the first
electrode pad 6-1a, and the hypotenuse of the right angled triangle
that forms the first electrode pad 6-2a, are opposed in the first
direction.
Embodiment 2
[0068] The touch panel 2 in the above-described embodiment can be
applied to a non-rectangular touch panel. FIG. 8 illustrates an
exemplary configuration in a case where the configuration of the
first electrodes 4, 6 and the second electrodes 5, 7 in Embodiment
1 described above, illustrated in FIG. 2, is applied to a
non-rectangular touch panel. In the example illustrated in FIG. 8,
an outer edge part of the touch panel 2 is curved. The frame area
outside the display area AA is in a non-rectangular shape. On outer
sides of an area R1 that overlaps the display area AA, lines 5c of
second electrodes 5-1 to 5-6 are arranged so as to be along the
display area AA. On further outer sides, in spaces between the
lines 5c and the outer edge of the touch panel 2, there are arrange
second electrode pads 7-1a to 7-6a and a plurality of first
electrode pads 6-1a and 6-2a that are opposed to these second
electrode pads 7-1a to 7-6a. The ends of the second electrode pads
7-1a to 7-6a and the first electrode pads 6-1a and 6-2a are in
shapes along the shape of the outer edge of the touch panel 2.
Embodiment 3
[0069] In Embodiments 1 and 2 described above, the configuration is
such that all of the second electrodes 5 in the area R1 are
connected with the second electrodes 7 in the areas R2. As a
modification example, the configuration may be such that part of
the second electrodes 5 in the areas R1 are connected to the second
electrodes 7 in the areas R2. Alternatively, the configuration may
be such that the second electrodes 5 in the area R1, and the second
electrodes 7 in the areas R2 are not connected, but they are
provided independently.
[0070] FIG. 9 illustrates an exemplary configuration in which the
second electrodes 5 in the area R1 and the second electrodes 7 in
the areas R2 are independently provided. In FIG. 9, the electrode
configuration in the area R1 can be the same as that illustrated in
FIG. 2. The second electrodes 5-1 to 5-6 in the area R1 are
connected to a TP controller 11a through the lines 5c arranged in
areas outside the area R1. The configurations of the first
electrode pads 6-1a and 6-2a, the lines 6-1c and 6-2c thereof, and,
the second electrode pads 7-1a to 7-6a in the areas R2 can be the
same as that illustrated in FIG. 2. The second electrode pads 7-1a
to 7-6a are connected to TP controllers 11b through the lines 7c
provided in the areas R2.
[0071] In the example illustrated in FIG. 9, the TP controller 11a
to which the first electrodes 4 and the second electrodes 5 in the
area R1 are connected, and the TP controller 11b to which the first
electrodes 6 and the second electrodes 7 in the areas R2 are
connected, are different. In other words, the first TP controller
11a, which controls signals of the first electrodes 4 and the
second electrodes 5 in the area R1 and detects an object in the
area R1, and the second TP controllers 11b, which controls signals
of the first electrodes 6 and the second electrodes 7 in the areas
R2 and detects an object in the areas R2, are provided
individually. The first TP controller 11a and the second TP
controllers 11b can be formed with, for example, individual
semiconductor chips, respectively. Alternatively, the first TP
controller 11a and the second TP controllers 11b may be formed
with, for example, identical semiconductor chips, and the system
configuration may be such that they can be independently
driven.
[0072] By independently providing the first TP controller 11a that
controls or processes signals of the electrodes in the area R1 and
the second TP controllers 11b that controls or processes signals of
the electrodes in the area R2 in this way, the driving in
accordance with respective detection properties of the area R1 and
the area R2 is facilitated.
[0073] For example, the configuration may be such that the TP
controller 11a is of a mutual capacitance type and detects a
capacitance between the first electrodes 4 and the second
electrodes 5 in the area R1, and the TP controller 11b is of a
self-capacitance type and detects capacitances of the first
electrodes 6 and the second electrodes 7 in the areas R2. The
mutual capacitance type determines a change in the electrostatic
capacitance between the first electrode and the second electrode so
as to detect approach or contact of an object. The self-capacitance
type determines respective electrostatic capacitances coupled with
the first electrode and the second electrode so as to detect
approach or contact of an object. By using different detection
types in the areas R1 and R2, different detection performances can
be achieved in the areas R1 and R2. For example, contact of an
object can be detected in the area R1, and highly-sensitive
detection such as hover detection, or highly accurate detection for
fingerprint authentication or the like can be performed in the
areas R2.
Embodiment 4
[0074] In the touch panels 2 according to Embodiments 1 to 3, third
electrodes can be provided additionally at positions that overlaps
the first electrodes 6 or the second electrodes 7 in the area R2.
With this, for example, a sensor that is capable of detecting an
object can be formed with the third electrodes, and the first
electrodes 6 or the second electrodes 7.
[0075] FIG. 10A is a cross-sectional view illustrating an exemplary
configuration in a case where third electrodes are provided
additionally on the touch panel 2 illustrated in FIGS. 3 and 4. In
the example illustrated in FIG. 10A, the third electrodes 8 are
provided at positions that overlap the first electrodes 6 when
viewed in a direction II vertical the display surface of the
display area AA. Between the first electrodes 6 and the third
electrodes 8, an insulating layer 15, an elastomer layer 16, and an
insulating layer 17 are formed in the stated order. FIG. 10B
illustrates an arrangement of the third electrodes 8 on the touch
panel 2 illustrated in FIG. 10A, when viewed in the direction II
vertical to the display surface. In the example illustrated in FIG.
10B, the third electrodes 8 are arranged in the areas R2, that is,
in the frame areas outside the display area AA, in the first
direction along the edges of the touch panel 2. The example
illustrated in FIGS. 10A and 10B has the configuration of the
example illustrated in FIGS. 3 and 4 further including the third
electrodes 8, but similarly, it may have the configuration
illustrated in FIGS. 1 and 2 further including the third electrodes
8.
[0076] In the example illustrated in FIG. 10A, since the elastomer
layer 16 is present between the first electrodes 6 and the third
electrodes 8 in the areas R2, the distance between the first
electrodes 6 and the third electrodes 8 changes according to
contact of an object. By detecting a change in the capacitances
that occurs in response to a change in the distance between the
first electrodes 6 and the third electrodes 8, the contact of an
object in the areas R2 can be detected.
[0077] The configuration of the sensor in which the third
electrodes 8 are used is not limited to that of the above-described
example. For example, in place of the elastomer layer 16, a
piezoelectric film may be arranged, whereby a pressure sensor can
be formed in the area R2. Alternatively, a touch detection sensor
can be formed with the third electrodes 8 and the first electrodes
6. For example, it is possible that a touch sensor with accuracy
higher than that in the area R1 can be formed with the third
electrodes 8 and the first electrodes 6 in the areas R2, so that
fingerprint authentication or the like can be performed in the
areas R2. Further alternatively, a sensor with sensitivity higher
than that in the area R1 can be formed with the third electrodes 8
and the first electrodes 6, so that hover detection or the like can
be performed in the area R2. Still further alternatively, the third
electrodes 8 may be arranged on edges of the display device 10,
whereby a sensor that detects contact or approach of an object on
the edge can be formed.
Embodiment 5
[0078] FIG. 11 illustrates a exemplary modification of the first
electrodes 6 and the second electrodes 7 in the areas R2. In the
example illustrated in FIG. 11, the shapes of the touch panel 2 and
the display area AA viewed in a direction vertical to the display
surface are non-rectangular shapes. More specifically, the edges
(ends) of the touch panel 2 and the display area AA include curved
parts. In this example, the touch panel 2 is in a circular shape,
but, for example, it may be in a shape that includes a curve part
and a linear part.
[0079] In an area that overlaps the display area AA, that is, an
area R1, the following are arranged: first electrodes 4-1 to 4-4
extending in a first direction (the transverse direction, that is,
the horizontal direction of the display screen, as an example, in
FIG. 11); and second electrodes 5-1 to 5-4 extending in a second
direction intersecting with the first direction (the longitudinal
direction, that is, the vertical direction of the display screen,
as an example, in FIG. 11). The first electrodes 4-1 to 4-4 and the
second electrodes 5-1 to 5-4 are provided in different layers. For
example, the first electrode 4-1 is connected, through a through
hole 4-1h, to a line 4-1c arranged in a different layer. The line
4-1c is connected to a TP controller 11c provided at an end part of
the touch panel 2.
[0080] In a frame area, that is, areas R2 outside the area R1, a
plurality of electrode pads 6-1 to 6-4 of the first electrodes 6,
and a plurality of electrode pads 7-1 and 7-2 of the second
electrodes 7 are alternately arranged along the edge of the touch
panel 2. In this example, two electrode pads (for example, 6-2,
6-3) of the first electrodes are provided so as to be opposed to
one electrode pad (for example, 7-1) of the second electrodes. The
two electrode pads (for example, 6-2, 6-3) of the first electrode
opposed to one electrode pad 7-1 of the second electrodes are
arranged along the edge of the touch panel 2. More specifically, in
the area R2, two first electrodes (for example, 6-2, 6-3) are
provided along the edge (outline) of the touch panel 2 so that the
second electrode 7-1 is interposed between the same on both
sides.
[0081] The plurality of electrode pads 6-1 to 6-4 of the first
electrode in each electrode pad area R2 are connected to the
plurality of first electrodes 4-1 to 4-4 in the area R1,
respectively. More specifically, the plurality of electrode pads
6-1 to 6-4 of the first electrode in the area R2 are connected,
through respective lines, to the TP controller 11c as an example of
the control unit. The second electrode pads 7-1 and 7-2 in the area
R2 are connected, through lines 7-1c and 7-2c arranged along the
display area AA, to the TP controller 11c.
[0082] FIG. 12 illustrates a modification example of the touch
panel 2 illustrated in FIG. 11. In the example illustrated in FIG.
12, two TP controllers 11d and 11e are provided at such positions
that they are opposed to each other so that the display area AA is
interposed therebetween. The electrode pads 6-1 to 6-4 of the
second electrodes in the areas R2 are connected to individual lines
6-1c to 6-4c arranged in the areas R2, respectively. Respective
ends of the first electrodes 4-1 to 4-4 in the area R1 are
connected to the first electrodes 6-1 to 6-4 in the areas R2,
respectively. To one of the two first electrodes 6-1 connected to
the respective ends of the first electrode 4-1, the line 6-1c is
connected. The lines 6-1c to 6-4c are formed so as to extend along
the edge of the touch panel 2, on the outer sides of the electrode
pads 6-1 to 6-4 of the first electrodes. By providing the two TP
controllers 11d and 11e at opposed positions in this way, the
lengths of the lines 6-1c to 6-4c can be decreased. This enables
more efficient line arrangement.
[0083] In a case where the shapes of the touch panel 2 and the
display area AA are not rectangular shapes but include curved
portions in the edges (outlines) thereof as in the present
embodiment, the first electrodes 6 and the second electrode 7
arranged so that one second electrode 7 is interposed between two
first electrodes 6 can be arranged in the areas R2 along the curves
of the edge of the display area AA or the touch panel 2. This makes
it possible to, in a non-rectangular touch panel as well,
efficiently arrange the electrodes in the frame area outside the
display area AA. In this way, the two or more first electrodes 6
provided so as to be opposed to one second electrode 7 in the area
R2 can be arrayed, not exclusively in the first direction, but, for
example, in the second direction, or in a direction different from
both of the first direction and the second direction.
Other Modification Examples
[0084] The embodiment of the present invention is not limited to
Embodiments 1 to 5. For example, in the areas R2, the configuration
can be such that one electrode pad of the first electrodes is
opposed to at least one second electrode. FIG. 13 illustrates an
exemplary modification of the electrode pads of the first
electrodes in the area R2 in the configuration illustrated in FIG.
1. In the example illustrated in FIG. 13, in the areas R2, one
electrode pad 6-1 of the first electrodes 6 is provided at such a
position that the electrode pad 6-1 is opposed to two second
electrodes 7-1 extending in the second direction. The electrode pad
6-1 is connected with the TP controller 11, through the line 6-1c
extending in the first direction.
[0085] Further, for example, the touch panel 2 can have such a
configuration that contact or approach of an object at an edge of
the transparent cover 2a is detected by the first electrodes 6 and
the second electrodes 7 in the areas R2. In the above-described
embodiments 1 to 5, it is possible to improve the detection
accuracy in the frame area, without an increase in the number of
lines in a frame area outside an area overlapping the display area
AA. This enables, for example, highly accurate edge detection.
Besides, this makes it possible to make the object detection
accuracy in the display area and the object detection accuracy at
the edge of the transparent cover outside the display area
different from each other. This makes it possible to realize
respective detection properties suitable for object detection, in
both of a part of transparent cover that overlaps the display area,
and an edge of the transparent cover.
[0086] Still further, the first electrodes 4 and the second
electrodes 5 in the area R1, and the first electrodes 6 and the
second electrodes 7 in the areas R2, can be formed in different
layers. This makes it possible to improve the degree of freedom in
designing first electrodes and the second electrodes in the area R1
and the areas R2.
[0087] In Embodiments 1 to 5, the display panel 1 may include a
first display area corresponding to the area R1 of the touch panel
2, and second display areas corresponding to the areas R2 of the
touch panel. In this case, the display device 10 can further
include the following: a first image generation unit that generates
an image to be displayed on the first display area based on the
position of an object detected in the area R1 of the touch panel 2;
and a first image generation unit that generates an image to be
displayed on the second display area based on the position of an
object detected in the area R2. This allows the display in the
second display area to be controlled independently from the display
in the first display area.
[0088] Still further, the display panel is not limited to the
liquid crystal panel. The display panel may be, for example, an
organic EL display, a plasma display, or a display in which
electrophoresis or MEMS is used.
Application Example
[0089] The embodiments of the present invention encompass various
types of electronic apparatuses in which the display device 10
according to any of Embodiments 1 to 5 is incorporated. For
example, the display device of the present invention can be applied
to smartphones, mobile phones, tablet terminals, game machines,
general-purpose computers, remote controllers for various types of
apparatuses, digital cameras, video cameras, on-vehicle panels, car
navigation systems, television apparatuses, ATMs, electronic
bulletin boards, electronic guideboards, electronic whiteboards,
and the like. Such various types of electronic apparatuses can
include touch panels having appropriate detection performance
suitable for the purpose of use of the electronic apparatuses, by
mounting thereon the display device 10 according to any of
Embodiments 1 to 5.
DESCRIPTION OF REFERENCE NUMERALS
[0090] 1 display panel [0091] 2 touch panel [0092] 4 first
electrode in first area [0093] 5 second electrode in first area
[0094] 6 first electrode in second area [0095] 7 second electrode
in second area [0096] 4c, 5c, 6c, 7c line [0097] 10 display device
[0098] 11 TP controller
* * * * *